Enlist Duo: EPA Approves Heinous Herbicide

Corn and soybean fields in Iowa, one of the states where herbicide Enlist Duo has been approved for use by the EPA.

TumblingRun / Flickr

Genetically engineered (GE) crops are making headlines again after the U.S. Department of Agriculture approved two varieties of genetically modified apples for planting and commercial sale that do not brown when cut or bruised. While we’ve been distracted by apples that may compete with fast-food hamburgers for longest shelf-life, a coalition of environmental groups and farmers has been tackling a different GMO-related problem known as “Enlist Duo.”

Monsanto's herbicide, Roundup, has been widely used to tackle weeds and contains the active ingredient glyphosate, now found in Enlist Duo.

Photo courtesy of Mike Mozart

In October 2014, the EPA approved Enlist Duo, a powerful herbicide, for use on GE corn and soybeans in six Midwest states. Enlist Duo has two active ingredients: 2,4-D and glyphosate. The first, 2,4-D, was infamously used during the Vietnam War as an active ingredient in Agent Orange. The second, glyphosate, is the active ingredient in Monsanto’s “Roundup” herbicides. These chemicals are now being combined in Enlist Duo to combat weeds that have developed a resistance to glyphosate.

Earthjustice and the Center for Food Safety filed a motion this month to stay the EPA’s approval of Enlist Duo on the grounds that the EPA violated the Endangered Species Act (ESA). Two of the many endangered species that call this region home are the whooping crane and Indiana bat. The EPA failed to consult with the U.S. Fish & Wildlife Service (FWS) regarding the impact of Enlist Duo on these or any other endangered species before approving it for use.

The ESA requires that every federal agency determine whether its actions “may affect” any endangered species or designated critical habitat. The EPA admitted that Enlist Duo may affect the whooping crane and Indiana bat. Unfortunately, it did not adhere to ESA protocol: if the action may affect an endangered species, the agency must then consult with FWS to “insure” that the action is “not likely to jeopardize the continued existence” of that species.

The whooping crane, a critically endangered species, is threatened by the toxic herbicide Enlist Duo.

Nancy Bauer / Shutterstock

The EPA found that during the whooping cranes’ migration the birds will stop to eat, and that they “may consume arthropod prey” exposed to 2,4-D in fields sprayed with Enlist Duo. Only FWS, and not EPA, is qualified and legally entitled to determine whether these hungry cranes and bats will consume the herbicide in toxic amounts.

With only an estimated 383 whooping cranes remaining in the wild, this animal needs stringent protection for its populations to have a chance at recovery. The same is true of the Indiana bat, which plays an important role in maintaining ecosystem balance. In addition to habitat loss and cave disturbance, scientists have attributed pesticide contamination of the Indiana bats’ food supply as a reason for their continued decline.

The bottom line: insects covered in 2,4-D should not be on the menu for either of these species, not to mention all of those other species not currently protected by the Endangered Species Act. The EPA has a responsibility to properly investigate the impacts of all herbicides that it approves for use, and chemicals known to be harmful to human, animal and plant life should not be flippantly rubber-stamped at the behest of the companies that profit from them.

Want to learn more about GMOs? Listen to the podcast below or click here to visit our feature story on GMOs, Engineering an Environmental Disaster. You can read more about other Earthjustice GMO cases here and here or explore Monsanto's seedy chemical history here.

Paul headed the Mid-Pacific regional office in Honolulu, HI, from 1994–2019. During that time, he handled a wide variety of public interest environmental litigation, including matters arising under the Endangered Species Act, National Environmental Policy Act, Clean Water Act, Migratory Bird Treaty Act, and Hawaiʻi’s Water Code.

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